﻿
/*
*      
*          ┌─┐       ┌─┐
*       ┌──┘ ┴───────┘ ┴──┐
*       │                 │
*       │       ───       │
*       │  ─┬┘       └┬─  │
*       │                 │
*       │       ─┴─       │
*       │                 │
*       └───┐         ┌───┘
*           │         │
*           │         │
*           │         │
*           │         └──────────────┐
*           │                        │
*           │                        ├─┐
*           │                        ┌─┘    
*           │                        │
*           └─┐  ┐  ┌───────┬──┐  ┌──┘         
*             │ ─┤ ─┤       │ ─┤ ─┤         
*             └──┴──┘       └──┴──┘ 
*                 神兽保佑 
*                 代码无BUG! 
*  Author shang
*  2022-07-21 18:09:27
*/

using System.Collections;
using System.Reflection;
using System.Text.RegularExpressions;
using Microsoft.Extensions.Caching.Memory;
using SqlSugar;

namespace TS.Common.Db;

public class HttpRuntimeCache :ICacheService
{
    MemoryCacheHelper cache = new ();

    public void Add<V>(string key, V value)
    {
        cache.Set(key, value);
    }

    public void Add<V>(string key, V value, int cacheDurationInSeconds)
    {
        cache.Set(key, value, cacheDurationInSeconds);
    }

    public bool ContainsKey<V>(string key)
    {
        return cache.Exists(key);
    }

    public V Get<V>(string key)
    {
        return cache.Get<V>(key);
    }

    public IEnumerable<string> GetAllKey<V>()
    {
        return cache.GetCacheKeys();
    }

    public V GetOrCreate<V>(string cacheKey, Func<V> create, int cacheDurationInSeconds = int.MaxValue)
    {
        if (cache.Exists(cacheKey))
        {
            return cache.Get<V>(cacheKey);
        }
        else
        {
            var result = create();
            cache.Set(cacheKey, result, cacheDurationInSeconds);
            return result;
        }
    }

    public void Remove<V>(string key)
    {
        cache.Remove(key);
    }
}

public class MemoryCacheHelper
{
    private static readonly MemoryCache Cache = new MemoryCache(new MemoryCacheOptions());

    /// <summary>
    /// 验证缓存项是否存在
    /// </summary>
    /// <param name="key">缓存Key</param>
    /// <returns></returns>
    public bool Exists(string key)
    {
        if (key == null)
            throw new ArgumentNullException(nameof(key));
        return Cache.TryGetValue(key, out _);
    }

    /// <summary>
    /// 添加缓存
    /// </summary>
    /// <param name="key">缓存Key</param>
    /// <param name="value">缓存Value</param>
    /// <param name="expiresSliding">滑动过期时长（如果在过期时间内有操作，则以当前时间点延长过期时间）</param>
    /// <param name="expiressAbsoulte">绝对过期时长</param>
    /// <returns></returns>
    public bool Set(string key, object value, TimeSpan expiresSliding, TimeSpan expiressAbsoulte)
    {
        if (key == null)
            throw new ArgumentNullException(nameof(key));
        if (value == null)
            throw new ArgumentNullException(nameof(value));

        Cache.Set(key, value,
            new MemoryCacheEntryOptions().SetSlidingExpiration(expiresSliding)
                .SetAbsoluteExpiration(expiressAbsoulte));
        return Exists(key);
    }

    /// <summary>
    /// 添加缓存
    /// </summary>
    /// <param name="key">缓存Key</param>
    /// <param name="value">缓存Value</param>
    /// <param name="expiresIn">缓存时长</param>
    /// <param name="isSliding">是否滑动过期（如果在过期时间内有操作，则以当前时间点延长过期时间）</param>
    /// <returns></returns>
    public bool Set(string key, object value, TimeSpan expiresIn, bool isSliding = false)
    {
        if (key == null)
            throw new ArgumentNullException(nameof(key));
        if (value == null)
            throw new ArgumentNullException(nameof(value));

        Cache.Set(key, value,
            isSliding
                ? new MemoryCacheEntryOptions().SetSlidingExpiration(expiresIn)
                : new MemoryCacheEntryOptions().SetAbsoluteExpiration(expiresIn));

        return Exists(key);
    }

    /// <summary>
    /// 添加缓存
    /// </summary>
    /// <param name="key">缓存Key</param>
    /// <param name="value">缓存Value</param>
    /// <returns></returns>
    public void Set(string key, object value)
    {
        Set(key, value, TimeSpan.FromDays(1));
    }

    /// <summary>
    /// 添加缓存
    /// </summary>
    /// <param name="key">缓存Key</param>
    /// <param name="value">缓存Value</param>
    /// <param name="ts"></param>
    /// <returns></returns>
    public void Set(string key, object value, TimeSpan ts)
    {
        Set(key, value, ts, false);
    }

    /// <summary>
    /// 添加缓存
    /// </summary>
    /// <param name="key">缓存Key</param>
    /// <param name="value">缓存Value</param>
    /// <param name="ts"></param>
    /// <returns></returns>
    public void Set(string key, object value, int seconds)
    {
        var ts = TimeSpan.FromSeconds(seconds);
        Set(key, value, ts, false);
    }

    #region 删除缓存

    /// <summary>
    /// 删除缓存
    /// </summary>
    /// <param name="key">缓存Key</param>
    /// <returns></returns>
    public void Remove(string key)
    {
        if (key == null)
            throw new ArgumentNullException(nameof(key));
        Cache.Remove(key);
    }

    /// <summary>
    /// 批量删除缓存
    /// </summary>
    /// <returns></returns>
    public void RemoveAll(IEnumerable<string> keys)
    {
        if (keys == null)
            throw new ArgumentNullException(nameof(keys));

        keys.ToList().ForEach(item => Cache.Remove(item));
    }

    #endregion

    #region 获取缓存

    /// <summary>
    /// 获取缓存
    /// </summary>
    /// <param name="key">缓存Key</param>
    /// <returns></returns>
    public T Get<T>(string key)
    {
        if (key == null)
            throw new ArgumentNullException(nameof(key));

        return Cache.Get<T>(key);
    }

    /// <summary>
    /// 获取缓存
    /// </summary>
    /// <param name="key">缓存Key</param>
    /// <returns></returns>
    public object Get(string key)
    {
        if (key == null)
            throw new ArgumentNullException(nameof(key));

        return Cache.Get(key);
    }

    /// <summary>
    /// 获取缓存集合
    /// </summary>
    /// <param name="keys">缓存Key集合</param>
    /// <returns></returns>
    public IDictionary<string, object> GetAll(IEnumerable<string> keys)
    {
        if (keys == null)
            throw new ArgumentNullException(nameof(keys));

        var dict = new Dictionary<string, object>();
        keys.ToList().ForEach(item => dict.Add(item, Cache.Get(item)));
        return dict;
    }

    #endregion

    /// <summary>
    /// 删除所有缓存
    /// </summary>
    public void RemoveCacheAll()
    {
        var l = GetCacheKeys();
        foreach (var s in l)
        {
            Remove(s);
        }
    }

    /// <summary>
    /// 删除匹配到的缓存
    /// </summary>
    /// <param name="pattern"></param>
    /// <returns></returns>
    public void RemoveCacheRegex(string pattern)
    {
        IList<string> l = SearchCacheRegex(pattern);
        foreach (var s in l)
        {
            Remove(s);
        }
    }

    /// <summary>
    /// 搜索 匹配到的缓存
    /// </summary>
    /// <param name="pattern"></param>
    /// <returns></returns>
    public IList<string> SearchCacheRegex(string pattern)
    {
        var cacheKeys = GetCacheKeys();
        var l = cacheKeys.Where(k => Regex.IsMatch(k, pattern)).ToList();
        return l.AsReadOnly();
    }

    /// <summary>
    /// 获取所有缓存键
    /// </summary>
    /// <returns></returns>
    public List<string> GetCacheKeys()
    {
        const BindingFlags flags = BindingFlags.Instance | BindingFlags.NonPublic;
        var entries = Cache.GetType().GetField("_entries", flags).GetValue(Cache);
        var cacheItems = entries as IDictionary;
        var keys = new List<string>();
        if (cacheItems == null) return keys;
        foreach (DictionaryEntry cacheItem in cacheItems)
        {
            keys.Add(cacheItem.Key.ToString());
        }

        return keys;
    }
}